Box-like containers are typically used to transport goods in interstate commerce. To ease burdens required in moving these containers by ship, train, truck, etc., the International Standards Organization (ISO) has required uniform dimensions. While many standard sizes have been approved by the ISO, containers having lengths of twenty feet and forty feet have gained widespread acceptance in the United States since they can be most easily and economically hauled over-the-road on trailers.
Commonly used to haul 40' ISO containers are trailers having a 40' gooseneck-type chassis with an elevated forward portions to accommodate the 5.sup.th wheel couplers of towing tractors. The elevated forward portion of the chassis carries a pair of rearwardly directed pins for attachment to specialized castings at the front of a 40' ISO container and the rearward portion of the chassis has a pair of vertically oriented twist locks for attachment to castings at the rear of the container. Unfortunately, this container attachment system does not permit a pair of 20' ISO containers positioned in tandem to be attached to the chassis thereby limiting its utility.